Information storage system

ABSTRACT

An information storage system which can be used by only those users who are previously permitted to access the system is provided. The information storage system has a first information storage device for accessing a first removable recording medium and a second information storage device for accessing a second removable recording medium. An access controller controls access to the first removable recording medium by the first information storage device based on a result of access to the second removable recording medium by the second information storage device prior to access to the first removable recording medium by the first information storage device.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an information storage system,and in particular to an information storage system which storesinformation in a removable recording medium.

[0003] 2. Description of the Related Art

[0004] Recently, a storage capacity of a removable recording mediumwhich is used in information storage systems has become large. Thus, alarge amount of information can be easily and quickly taken away bybeing recorded on the removable recording medium. For this reason, it isdesired to improve security for information.

[0005] In a large-scale computer, security of the system can bemaintained since the places in which the system is installed arerelatively limited and only people having permission can enter thoseplaces. Additionally, a user is required to enter a password in order toaccess important data. Thus, it is not easy to access information in thecase of the large-scale computer.

[0006] On the other hand, a personal computer, which has rapidly becomewide spread, can be set in any place and anyone can easily access thesystem. With the recent spread of the personal computer, important datahas become handled by the personal computer. Additionally, a storagecapacity of a storage device of a removable recording medium type usedin the personal computer has become large. For example, it is possibleto record 640 MB of data in a single recording medium in the case of anoptical disk apparatus such as a phase-change type optical disk (PD)apparatus and a magneto-optic disk apparatus, or a large capacity floppydisk apparatus.

[0007]FIG. 1 shows a system structure diagram of an example of aconventional information processing system. In the conventional system50, a magneto-optic disk apparatus 52 is connected to a personalcomputer 51 via a SCSI interface. Information is recorded on andreproduced from a magneto-optic disk 53 which is mounted in themagneto-optic disk apparatus 52. In the conventional informationprocessing system 50, no security is provided for the magneto-optic diskapparatus 52.

[0008] Therefore, if no security is provided for the personal computer51, important data stored in a built-in hard disk of the personalcomputer 51 can be taken away by copying the data to the magneto-opticdisk 53 by means of the magneto-optic disk apparatus 52. In this case, alarge amount of data corresponding to an amount of data stored inseveral hundred floppy disks can be quickly and secretly taken away,because the magneto-optic disk 53 has a maximum capacity as large as 640MB or even 1.3 GB.

[0009] Additionally, data which is stored in the magneto-optic disk 53can be instantly copied or deleted. The conventional informationprocessing system 50 has no protection against such a situation.

SUMMARY OF THE INVENTION

[0010] Accordingly, it is an object of the present invention to providean information storage system which can be used by only those users whoare previously permitted to access the system.

[0011] The above-mentioned object of the present invention can beachieved by an information storage system comprising:

[0012] a first information storage device for accessing a firstremovable recording medium;

[0013] a second information storage device for accessing a secondremovable recording medium; and

[0014] an access controller for controlling access to the firstremovable recording medium by the first information storage device basedon a result of access to the second removable recording medium by thesecond information storage device prior to access to the first removablerecording medium by the first information storage device.

[0015] According to the invention, since access to the first removablerecording medium is permitted in accordance with the result of access tothe second removable recording medium, a user who does not have thesecond removable recording medium cannot access the first removablerecording medium. Hence, the security provided for information of thefirst information storage device can be improved.

[0016] In the above information storage system, the second informationstorage device may comprise a medium detector for detecting the secondremovable recording medium mounted in a predetermined position where thesecond removable recording medium can be accessed by the secondinformation storage device.

[0017] In this case, the access controller may permit the firstinformation storage device to access the first removable recordingmedium when the medium detector detects the second removable recordingmedium mounted in the predetermined position.

[0018] According to the invention, since access to the first removablerecording medium is permitted when the medium detector detects thesecond removable recording medium mounted in the second informationstorage device, a user who does not have the second removable recordingmedium cannot access the first removable recording medium. Hence, thesecurity provided for information of the first information storagedevice can be improved.

[0019] The access controller may turn on power supply to the firstinformation storage device when the medium detector detects the secondremovable recording medium mounted in the predetermined position.

[0020] According to the invention, when the second removable recordingmedium is not mounted in the second information storage device, thefirst information storage device cannot access the first removablerecording medium since the first information storage device is notsupplied with power. Hence, a user who does not have the secondremovable recording medium cannot access the first removable recordingmedium, and as a result, the security provided for information of thefirst information storage device can be improved.

[0021] In the above-mentioned information storage system, the secondinformation storage device may comprise a information reader for readingout information recorded on the second removable recording medium.

[0022] In this case, the second removable recording medium may beprovided with access permission information recorded thereon; and

[0023] the access controller may control access to the first removablerecording medium by the first information storage device based on theaccess permission information read by the information reader.

[0024] According to the invention, since access to the first removablerecording medium is controlled in accordance with the access permissioninformation recorded on the second removable recording medium, thesecurity provided for information of the first information storagedevice can be improved.

[0025] The access permission information may comprise write permissioninformation for permitting the first information storage device to writeinformation to the first removable recording medium.

[0026] In this case, the access controller may permit the firstinformation storage device to write information to the first removablerecording medium when the write permission information is valid.

[0027] According to the invention, write access to the first removablerecording medium by the first information storage device can berestricted based on the write permission information. Hence, it ispossible to prevent information from being taken away after having beenrecorded on the first removable recording medium, and thus, the securityprovided for information of the first information storage device can befurther improved.

[0028] The access permission information may comprise read permissioninformation for permitting the first information storage device to readinformation from the first removable recording medium.

[0029] In this case, the access controller may permit the firstinformation storage device to read information from the first removablerecording medium when the read permission information is valid.

[0030] According to the invention, read access to the first removablerecording medium by the first information storage device can berestricted based on the read permission information. Hence, it ispossible to prevent information from being easily read out from thefirst removable recording medium, and thus, the security provided forinformation of the first information storage device can be improved.

[0031] The access permission information may comprise a control programfor controlling the access controller; and

[0032] the access controller may control access to the first removablerecording medium by the first information storage device in accordancewith the control program.

[0033] According to the invention, since the first removable recordingmedium cannot be accessed without the second removable recording mediumbeing provided with the control program recorded thereon, the securityprovided for information of the first information storage device can beimproved.

[0034] The information storage system may further comprise a controlprogram setting part for validating or invalidating the control program.

[0035] In this case, the access controller may control access to thefirst removable recording medium by the first information storage devicein accordance with the control program when the control program isvalidated by the control: program setting part; and

[0036] the access controller may control access to the first removablerecording medium by the first information storage device irrespective ofthe control program when the control program is invalidated by thecontrol program setting part.

[0037] According to the invention, since the control program can beeasily validated or invalidated by the control program setting part, itis possible to change an extent of the security in accordance withvarious situations.

[0038] The above-mentioned object can also be achieved by an informationstorage system comprising:

[0039] a first information storage device for accessing a firstremovable recording medium;

[0040] a second information storage device for accessing a secondremovable recording medium to read out first access permissioninformation recorded on the second removable recording medium;

[0041] an access permission information storage part for storing secondaccess permission information; and

[0042] an access controller for permitting the first information storagedevice to access the first removable recording medium when the firstaccess permission information read out by the second information storagedevice and the second access permission information stored in the accesspermission information storage part satisfy a predetermined condition.

[0043] According to the present invention, the access to the firstremovable recording medium by the first information storage device canbe controlled in accordance with the first access permission informationrecorded on the second removable recording medium and the second accesspermission information stored in the access permission informationstorage part. Thus, more sophisticated access control can be achieved sothat the security provided for information of the first informationstorage device is further improved.

[0044] In the above information storage system, the access controllermay permit the first information storage device to access the firstremovable recording medium when the first access permission informationcorresponds to the second access permission information.

[0045] According to the present invention, the first removable recordingmedium can be accessed by only those who have the second removablerecording medium containing the first access permission informationcorresponding to the second access permission information stored in theaccess permission information storage part. Thus, the security providedfor information of the first information storage device can be improved.

[0046] The first access permission information may comprise writepermission information for permitting the first information storagedevice to write information to the first removable recording medium.

[0047] According to the invention, since write access to the firstremovable recording medium can be restricted based on the writepermission information, it is possible to prevent information from beingtaken away after having been recorded on the first removable recordingmedium. Thus, the security provided for information of the firstinformation storage device can be further improved.

[0048] The first access permission information may comprise readpermission information for permitting the first information storagedevice to read information from the first removable recording medium.

[0049] According to the invention, since read access to the firstremovable recording medium can be restricted based on the readpermission information, it is possible to prevent information from beingeasily read out from the first removable recording medium. Thus, thesecurity provided for information of the first information storagedevice can be further improved.

[0050] The access controller may permit the first information storagedevice to write information to the first removable recording medium whenthe write permission information is valid.

[0051] According to the invention, security against write access to thefirst removable recording medium can be easily changed based on thewrite permission information.

[0052] The access controller may permit the first information storagedevice to read information from the first removable recording mediumwhen the read permission information is valid.

[0053] According to the invention, security against read access to thefirst removable recording medium can be easily changed based on the readpermission information.

[0054] The first access permission information may comprise a controlprogram for controlling the access controller; and

[0055] the access controller may control access to the first removablerecording medium by the first information storage device in accordancewith the control program.

[0056] According to the invention, since the first removable recordingmedium cannot be accessed without the second removable recording mediumprovided with the control program recorded thereon, the securityprovided for information of the first information storage device can beimproved.

[0057] The information storage system may further comprise a controlprogram setting part for validating or invalidating the control program.

[0058] In this case, the access controller controls access to the firstremovable recording medium by the first information storage device inaccordance with the control program when the control program isvalidated by the control program setting part; and

[0059] the access controller controls access to the first removablerecording medium by the first information storage device irrespective ofthe control program when the control program is invalidated by thecontrol program setting part.

[0060] According to the invention, the access controller controls accessto the first removable recording medium based on the validity of thecontrol program. Thus, it is possible to change an extent of thesecurity against access to the first removable recording medium inaccordance with various situations.

[0061] Other objects and further features of the present invention willbe apparent from the following detailed description when read inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0062]FIG. 1 is a system structure diagram of a conventional informationprocessing system;

[0063]FIG. 2 is a system structure diagram of an information storagesystem of an embodiment according to the present invention;

[0064]FIG. 3 is a block diagram of the information storage system of theembodiment according to the present invention;

[0065]FIG. 4 is a diagram showing a data structure of a user IDmanagement table of the embodiment according to the present invention;

[0066]FIG. 5 is a schematic structure diagram of an IC card of theembodiment according to the present invention;

[0067]FIG. 6 is a diagram showing a data structure of the IC card of theembodiment according to the present invention;

[0068]FIG. 7 is a flowchart of an operation of an MO controller of theembodiment according to the present invention; and

[0069]FIG. 8 is a block diagram of an information storage system ofanother embodiment according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0070]FIG. 2 shows a system structure diagram of an informationprocessing system 1 of an embodiment of the present invention. In theinformation processing system 1, an information storage system 2according to the present invention is connected to a personal computer3.

[0071] The information storage system 2 includes a magneto-optic diskrecording and reproducing unit 5 and an IC card reader unit 7, both ofwhich are attached to a housing 8. A magneto-optic disk cartridge 4containing a magneto-optic disk is mounted in the magneto-optic diskrecording and reproducing unit 5. The unit 5 records and reproduces dataon the magneto-optic disk. On the other hand, an IC card 6 is mounted inthe IC card reader unit 7. The IC card reader unit 7 controls theoperation of the magneto-optic disk recording and reproducing unit 5.

[0072]FIG. 3 is a block diagram of the information storage system 2 ofthe present embodiment. Connectors 11, 12 are provided on a rear face ofthe magneto-optic disk recording and reproducing unit 5. The connector11 is connected to a SCSI connector of the personal computer 3 via aSCSI cable 13. On the other hand, the connector 12 is connected to aterminator 15. The SCSI connector, which is provided integrally with aSCSI board, is exposed on a rear face of the personal computer 3.

[0073] The SCSI board is mounted in an extension slot inside thepersonal computer 3 for connecting with an ISA bus or a PCI bus, andprovides an interface between the personal computer 3 and a deviceconnected to the SCSI connector.

[0074] The connectors 11, 12 are connected to an interface circuit 14inside the magneto-optic disk recording and reproducing unit 5. Theinterface circuit 14 identifies an ID which is previously assigned tothe apparatus, and establishes a connection between the magneto-opticdisk recording and reproducing unit 5 and the personal computer 3.

[0075] When another apparatus is to be connected through the SCSI, aconnector of that apparatus is connected to the connector 12. Otherwise,a terminator 15 is connected to the connector 12.

[0076] The interface circuit 14 is connected to an MO controller 16. TheMO controller 16 controls recording and reproduction of information onthe magnet-optic disk 17 based on a command issued by the personalcomputer 3.

[0077] In addition to the interface circuit 14, a RAM 18, a ROM 19, auser ID management table 20, a bias coil driver 21, an optical systemdriver 22, an actuator driver 23, a focusing and tracking actuatordriver 24, a spindle driver 25, the IC card reader unit 7 and a dipswitch 36 are connected to the MO controller 16.

[0078] A control program for controlling recording and reproduction ofthe magneto-optic disk 17 is expanded in the RAM 18. Additionally, theRAM 18 temporarily stores data which is supplied from the interfacecircuit 14 and data which is to be transferred through the interfacecircuit 14 to the personal computer 3. On the other hand, the ROM 19contains an initializing program and various programs for controllingthe MO controller 16.

[0079] The user ID management table 20 manages IDs of users who arepermitted to use the information storage system 2. FIG. 4 shows a datastructure of the user ID management table 20 of the present embodiment.As shown in FIG. 4, IDs comprising 8 digit alphanumeric letters such as“9600001A” and “9600002A”, which are identical to IDs of IC cards ownedby the users who are permitted to use the information storage system 2,are previously registered in the user ID management table 20. In a casewhere a plurality of users are permitted to use the information storagesystem 2, a plurality of IDs are registered in the user ID managementtable 20 as shown in FIG. 4.

[0080] In the system shown in FIG. 3, the bias coil driver 21 supplies abias current to a bias coil 26 in response to a control signal deliveredfrom the MO controller 16. The bias coil 26 applies a bias magneticfield to the magneto-optic disk 17 when information is recorded.

[0081] The optical system driver 22 supplies an operating signal to anoptical system 27 in response to a control signal delivered from the MOcontroller 16. The optical system 27 generates a laser light which is tobe applied to the magneto-optic disk 17 when information is recorded orreproduced.

[0082] The actuator driver 23 supplies an operating signal to anactuator 29 in response to a control signal delivered from the MOcontroller 16. The actuator 29 actuates the bias coil 26 along with anoptical pickup 28 in a radial direction (a direction shown by an arrowA) of the magneto-optic disk 17. The optical pickup 28 projects thelaser light supplied from the optical system 27 onto the magneto-opticdisk 17 while controlling focusing and tracking of the laser light.

[0083] The focusing and tracking actuator driver 24 supplies anoperating signal to the optical pickup 28 in response to a controlsignal delivered from the MO controller 16. The optical pickup 28controls the focusing and tracking in accordance with the operatingsignal supplied from the driver 24.

[0084] The IC card reader unit 7 comprises a contact part 33, an IC cardcontroller 34, and an IC card insertion detecting switch 35. The contactpart 33 provides a connection to a contact 32 of an IC card 31. The ICcard controller 34 is connected to the contact part 33 and provides aninterface to the IC card 31. The IC card insertion detecting switch 35detects the IC card 31 inserted in a predetermined position of the ICcard reader unit 7.

[0085]FIG. 5 shows a schematic structure diagram of the IC card 31. TheIC card 31 (6) comprises an LSI (Large Scale Integration) circuit 37 andelectrodes 38. The LSI is embedded in a plastic card 39. The electrodes38 are connected to the LSI circuit 37 and exposed on the surface of theIC card 31. The LSI 37 is integrally formed with a RAM, a ROM, anEEPROM, a CPU and an interface circuit, and is connected to an externalcircuit via the electrodes 38. The EEPROM of the IC card 31 containsdata such as a name or an ID of an owner of the IC card 31.

[0086]FIG. 6 shows a diagram for illustrating contents of the EEPROM ofthe IC card 31. The EEPROM of the IC card 31 is provided with first toseventh fields as follows.

[0087] The first field has a data size of 32 bytes, and a user name isrecorded therein, for example, in an ASCII code.

[0088] The second field has a data size of 8 bytes, and the useridentification number is recorded therein, for example, in an ASCIIcode.

[0089] The third field has a data size of 1 byte, and the access rightrelating to read access is recorded in the first bit while the accessright relating to write access is recorded in the second bit, with “1”indicating valid and “0” indicating invalid, for example. The other bitsof the third field are reserved.

[0090] The fourth field has a data size of 7 bytes and is reserved.

[0091] The fifth field has a data size of 64 bytes and stores a headerfor transmitting the data recorded on the next (sixth) field.

[0092] The sixth field has a data size of 512 Kbytes and stores acontrol program such as a program for encryption.

[0093] The seventh field corresponds to the remaining part of the EEPROMand is reserved.

[0094] When the IC card 31 is inserted in the predetermined position ofthe IC card reader unit 7 of the information storage system 2, theelectrodes 38 are brought into contact with the contact part 33 so thatelectric power and a control signal are supplied to the IC card 31 fromthe IC card controller 34. In this case, the IC card 31 outputs thecontents of the memory to the IC card controller 34 in response to thecontrol signal supplied therefrom.

[0095] The IC card controller 34 is connected to the MO controller 16,and supplies the data read out from the IC card 31 to the MO controller16. Additionally, the MO controller 16 is connected to the IC cardinsertion detecting switch 35 and the dip switch 36. The dip switch 36is used to set whether the control program stored in the IC card 31 isto be used or not.

[0096] The MO controller 16 controls a response to an access commandissued by the personal computer 3 in accordance with a state of the ICcard insertion detecting switch 35, a state of the dip switch 36 and thecontents of the memory of the IC card 31.

[0097]FIG. 7 shows a flowchart of an operation of the MO controller 16when the magneto-optic disk 17 is accessed. When the personal computer 3demands to access the magneto-optic disk 17, it issues a “test unitready” command. When the “test unit ready” command is issued by thepersonal computer 3 in step S1-1, the MO controller 16 determineswhether or not the IC card 31 is inserted based on the state (ON or OFF)of the IC card insertion detecting switch 35 in step S1-2.

[0098] If it is determined that the IC card 31 is not inserted in stepS1-2, a command error signal is returned to the personal computer 3 instep S1-3. When the command error signal is returned to the personalcomputer 3 in response to the “test unit ready” command, the personalcomputer 3 only recognizes that the magneto-optic disk cartridge 4 isnot inserted, and this has no disadvantageous effect on the personalcomputer 3. In this case, the personal computer 3 may display a messagefor prompting a user to insert the IC card or a message such as “Thismagneto-optic disk cartridge cannot be used.” to indicate that writeaccess is not permitted

[0099] If, in step S1-2, it is determined that the IC card 31 isinserted, then in step S1-4, the MO controller 16 controls the IC cardcontroller 34 to read the contents of the IC card 31. The data read outfrom the IC card 31 is supplied to the MO controller 16 via the IC cardcontroller 34 and stored in the RAM 18.

[0100] In the next step S1-5, it is determined whether or not the userID of the IC card 31 is registered in the user ID management table 20,that is, whether or not the user who has inserted the IC card 31 ispermitted to use the information storage system 2, by comparing the userID of the IC card 31 with the contents of the user ID management table20. If the user ID of the IC card 31 is not registered in the user IDmanagement table 20 in step S1-5, an error signal is returned to thepersonal computer 3 in step S1-3. On the other hand, if the user ID ofthe IC card 31 is registered in the user ID management table 20, a readycommand is returned to the personal computer 3 to indicate that accessto the magneto-optic disk 17 is permitted.

[0101] In the next step S1-7, the MO controller 16 detects the state ofthe dip switch 36. If the dip switch 36 is set in a state to use thecontrol program stored in the IC card 31, the control program is readout from the IC card 31 through the IC card controller 34, expanded inthe RAM 18 and then started in step S1-8.

[0102] In the present embodiment, the determination whether or not thecontrol program is to be used is made based on the state of the dipswitch 36 provided to the system. However, the determination may be madebased on control program setting information stored in the IC card 31.Additionally, the control program setting information may be stored inthe ROM 19 instead of the IC card 31.

[0103] If, in step S1-7, the dip switch 36 is not set in the state touse the control program stored in the IC card 31, the control program isnot started.

[0104] If an access command is delivered from the personal computer 3 instep S1-9, the MO controller 16 determines whether the access commandrelates to read access or write access in step S1-10. If the accesscommand relates to read access, then it is determined whether or not theuser of the IC card 31 inserted in the IC card reader unit 7 ispermitted to make read access in step S1-11. The determination in stepS1-11 is made by checking whether the first bit of the access rightinformation (the third field) in the IC card 31 is valid(“1”) or invalid(“0”). If the first bit of the access right information in the IC card31 is invalid, an error signal is returned to the personal computer 3 instep S1-12. On the other hand, if the first bit of the access rightinformation is valid, read access to the magneto-optic disk 17 ispermitted in step S1-13.

[0105] If, in step S1-10, the access command delivered from the personalcomputer 3 relates to write access, then it is determined whether theuser of the IC card 31 inserted in the IC card reader unit 7 ispermitted to make write access in step S1-14. The determination in stepS1-14 is made by checking whether the second bit of the access rightinformation (the third field) in the IC card 31 is valid(“1”) or invalid(“0”). If the second bit of the access right information in the IC card31 is invalid, an error signal is returned to the personal computer 3 instep S1-12. On the other hand, if the second bit of the access rightinformation is valid, write access to the magneto-optic disk 17 ispermitted in step S1-15.

[0106] If write access is performed after the control program forencryption contained in the IC card 31 is started in steps S1-8, dataencoded by the control program is recorded on the magneto-optic disk 17.In this case, the data recorded on the magneto-optic disk 17 cannot becorrectly read out without decoding by the same control program. Thus,by setting the dip switch 36 so as to use the control program, it ispossible to permit only the users who have the IC card 31 containing thesame control program to read information from the magneto-optic disk 17among those who are permitted to access the information storage system2.

[0107] As described above, according to the information storage system 2of the present embodiment, the personal computer 3 cannot access themagneto-optic disk 17 unless the IC card 31 is inserted in the IC cardreader unit 7. Additionally, when the IC card 31 is inserted in the ICcard reader unit 7, the personal computer 3 cannot access themagneto-optic disk 17 unless the user ID recorded on the IC card 31 isregistered in the user ID management table 20 of the information storagesystem 2, that is, unless the user is permitted to use the informationstorage system 2. Further, when the user ID recorded on the IC card 31is registered in the user ID management table 20, data cannot be freelyread out from the magneto-optic disk 17 since the access isindependently permitted for read access and write access based on theaccess right information contained in the IC card 31. Still further, byusing the control program for encryption contained in the IC card 31,information can be prevented from being read out from the magneto-opticdisk 17, even if the information storage system 2 can be accessed.

[0108] Thus, it is possible to prevent a large amount of informationfrom being taken away after having been copied to the magneto-optic disk17.

[0109] It should be noted that execution of the encryption can bereadily cancelled by changing the state of the dip switch 36 so that thesystem can be used as an open system.

[0110] Now a description will be given of second embodiment according tothe present invention. FIG. 8 is a block diagram of an informationstorage system 41 of the second embodiment according to the presentinvention. In FIG. 8, parts corresponding those of FIG. 3 are given thesame reference numerals and descriptions thereof will be omitted.

[0111] In the above first embodiment, an error signal is supplied to thepersonal computer 3 in response to the access command when the IC cardinsertion detecting switch 35 is in an OFF state, that is, when the ICcard 31 is not inserted in the predetermined position of the IC cardreader unit 7. On the contrary, in the present embodiment, power supplyto the information storage system 41 is not turned on when the IC cardinsertion detecting switch 35 is in an OFF state.

[0112] In the information storage system 41 of the present embodiment,the IC card insertion detecting switch 35 is connected to a power supplycircuit 42 for supplying power to each part of the information storagesystem 41.

[0113] A main switch 43 is connected to the power supply circuit 42. Thepower supply circuit 42 is supplied with a power supply voltage Vcc viathe main switch 43 and the IC card insertion detecting switch 35 whichare connected in series. Thus, only when both the main switch 43 and theIC card insertion detecting switch 35 are turned on, the power supplycircuit 42 supplies power to each part of the information storage system41. Hence, if the main switch 43 is turned on, the information storagesystem 41 is not supplied with power when the IC card insertiondetecting switch 35 is in an OFF state, that is, when the IC card 31 isnot inserted the predetermined position of the IC card reader unit 7.

[0114] In the present embodiment, the information storage system 41 isnot supplied with power when the IC card insertion detecting switch 35is in an OFF state, as described above. Thus, according to the presentembodiment, when the IC card 31 is not inserted in the predeterminedposition of the IC card reader unit 7, the personal computer 3 cannotaccess the information storage system 41 even if the main switch 43 isturned on.

[0115] In the present embodiment, it is not necessary for the MOcontroller 16 to detect the state of the IC card insertion detectingswitch 35. Thus, the MO controller 16 operates according to theflowchart shown in FIG. 6 with step S1-2 being omitted.

[0116] It should be noted that the above-mentioned embodiments can beeasily implemented without changing application programs contained inthe personal computer 3.

[0117] In the above embodiments, the access right information is storedin the IC card 31. However, an other medium such as anothermagneto-optic disk or a floppy disk may be used instead of the IC card31 by providing a corresponding reader unit.

[0118] Additionally, in the above embodiments, the information storagesystem according to the present invention is constructed as amagneto-optic disk apparatus. However, the present invention can also beapplied to other types of information storage systems which operate withother types of removable recording media such as a phase-change typeoptical disk, a DVD-ROM/RAM, or a floppy disk.

[0119] Further, although the personal computer 3 is connected via theSCSI interface in the above-mentioned embodiments, it is also possibleto use other types of interfaces.

[0120] Still further, in the above embodiments, the IC card 31 and theIC card reader unit 7 are of a contact type. However, the IC card andthe IC card reader may be of a non-contact type or of a combined type ofthese two types.

[0121] Additionally, the IC card reader and the magneto-optic diskrecording and reproducing apparatus need not be integrally constructed,but they may be constructed as separate units so long as the accessright information can be transmitted therebetween.

[0122] Further, the present invention is not limited to theseembodiments, but variations and modifications may be made withoutdeparting from the scope of the present invention.

[0123] The present application is based on Japanese priority applicationNo. 10-2595 filed on Jan. 8, 1998, the entire contents of which arehereby incorporated by reference.

What is claimed is
 1. An information storage system comprising: a firstinformation storage device for accessing a first removable recordingmedium; a second information storage device for accessing a secondremovable recording medium; and an access controller for controllingaccess to said first removable recording medium by said firstinformation storage device based on a result of access to said secondremovable recording medium by said second information storage deviceprior to access to said first removable recording medium by said firstinformation storage device.
 2. The information storage system as claimedin claim 1, wherein: said second information storage device comprises amedium detector for detecting said second removable recording mediummounted in a predetermined position where said second removablerecording medium can be accessed by said second information storagedevice.
 3. The information storage system as claimed in claim 2,wherein: said access controller permits said first information storagedevice to access said first removable recording medium when said mediumdetector detects said second removable recording medium mounted in saidpredetermined position.
 4. The information storage system as claimed inclaim 2, wherein: said access controller turns on power supply to saidfirst information storage device when said medium detector detects saidsecond removable recording medium mounted in said predeterminedposition.
 5. The information storage system as claimed in claim 1,wherein: said second information storage device comprises an informationreader for reading out information recorded on said second removablerecording medium.
 6. The information storage system as claimed in claim5, wherein: said second removable recording medium is provided withaccess permission information recorded thereon; and said accesscontroller controls access to said first removable recording medium bysaid first information storage device based on said access permissioninformation read by said information reader.
 7. The information storagesystem as claimed in claim 6, wherein: said access permissioninformation comprises write permission information for permitting saidfirst information storage device to write information to said firstremovable recording medium.
 8. The information storage system as claimedin claim 6, wherein: said access permission information comprises readpermission information for permitting said first information storagedevice to read information from said first removable recording medium.9. The information storage system as claimed in claim 7, wherein: saidaccess controller permits said first information storage device to writeinformation to said first removable recording medium when said writepermission information is valid.
 10. The information storage system asclaimed in claim 8, wherein: said access controller permits said firstinformation storage device to read information from said first removablerecording medium when said read permission information is valid.
 11. Theinformation storage system as claimed in claim 6, wherein: said accesspermission information comprises a control program for controlling saidaccess controller; and said access controller controls access to saidfirst removable recording medium by said first information storagedevice in accordance with said control program.
 12. The informationstorage system as claimed in claim 11, further comprising: a controlprogram setting part for validating or invalidating said controlprogram.
 13. The information storage system as claimed in claim 12,wherein: said access controller controls access to said first removablerecording medium by said first information storage device in accordancewith said control program when said control program is validated by saidcontrol program setting part; and said access controller controls accessto said first removable recording medium by said first informationstorage device irrespective of said control program when said controlprogram is invalidated by said control program setting part.
 14. Aninformation storage system comprising: a first information storagedevice for accessing a first removable recording medium; a secondinformation storage device for accessing a second removable recordingmedium to read out first access permission information recorded on saidsecond removable recording medium; an access permission informationstorage part for storing second access permission information; and anaccess controller for permitting said first information storage deviceto access said first removable recording medium when said first accesspermission information read out by said second information storagedevice and said second access permission information stored in saidaccess permission information storage device satisfy a predeterminedcondition.
 15. The information storage system as claimed in claim 14,wherein: said access controller permits said first information storagedevice to access said first removable recording medium when said firstaccess permission information corresponds to said second accesspermission information.
 16. The information storage system as claimed inclaim 14, wherein: said first access permission information compriseswrite permission information for permitting said first informationstorage device to write information to said first removable recordingmedium.
 17. The information storage system as claimed in claim 14,wherein: said first access permission information comprises readpermission information for permitting said first information storagedevice to read information from said first removable recording medium.18. The information storage system as claimed in claim 16, wherein: saidaccess controller permits said first information storage device to writeinformation to said first removable recording medium when said writepermission information is valid.
 19. The information storage system asclaimed in claim 17, wherein: said access controller permits said firstinformation storage device to read information from said first removablerecording medium when said read permission information is valid.
 20. Theinformation storage system as claimed in claim 14, wherein: said firstaccess permission information comprises a control program forcontrolling said access controller; and said access controller controlsaccess to said first removable recording medium by said fist informationstorage device in accordance with said control program.
 21. Theinformation storage system as claimed in claim 20, further comprising: acontrol program setting part for validating or invalidating said controlprogram.
 22. The information storage system as claimed in claim 21,wherein: said access controller controls access to said first removablerecording medium by said first information storage device in accordancewith said control program when said control program is validated by saidcontrol program setting part; and said access controller controls accessto said first removable recording medium by said first informationstorage device irrespective of said control program when said controlprogram is invalidated by said control program setting part.
 23. Anapparatus which can be connected to a first information storage devicefor accessing a first removable recording medium and a secondinformation storage device for accessing a second removable recordingmedium, comprising: an access controller for controlling access to saidfirst removable recording medium by said first information storagedevice based on a result of access to said second removable recordingmedium by said second information storage device prior to access to saidfirst removable recording medium by said first information storagedevice.
 24. An access controlling method on an apparatus which can beconnected to a first information storage device for accessing a firstremovable recording medium and a second information storage device foraccessing a second removable recording medium, comprising: controllingaccess to said first removable recording medium by said firstinformation storage device based on a result of access to said secondremovable recording medium by said second information storage deviceprior to access to said first removable recording medium by said firstinformation storage device.